{"id":"EEF-CVE-2026-47074","summary":"ex_aws_sns SigningCertURL not validated in verify_message/1","details":"## Summary\n\nImproper Certificate Validation vulnerability in ex-aws ex\\_aws\\_sns (ExAws.SNS, ExAws.SNS.PublicKeyCache modules) allows Signature Spoofing by Improper Validation.\n\nThis vulnerability is associated with program files lib/ex\\_aws/sns.ex, lib/ex\\_aws/sns/public\\_key\\_cache.ex and program routines 'Elixir.ExAws.SNS':verify\\_message/1, 'Elixir.ExAws.SNS.PublicKeyCache':get/1.\n\n'Elixir.ExAws.SNS':verify\\_message/1 fetches the signing certificate from the SigningCertURL field of the incoming SNS message without validating that the URL uses HTTPS or that the host matches an AWS-owned SNS certificate domain. An unauthenticated attacker who can POST to an endpoint that calls verify\\_message/1 can supply an attacker-controlled SigningCertURL, sign a forged SNS message with their own key, and cause the function to return :ok, completely bypassing SNS signature verification.\n\nThis issue affects ex\\_aws\\_sns: from 2.0.1 before 2.3.5.\n\n## Configurations\n\nThe application must expose an HTTP endpoint that calls 'Elixir.ExAws.SNS':verify\\_message/1 on incoming request bodies.","aliases":["CVE-2026-47074","GHSA-8jgf-23q5-x7xx"],"modified":"2026-09-08T03:45:07.615311335Z","published":"2026-05-28T09:05:54.815Z","database_specific":{"capec_ids":["CAPEC-473"],"cpe_ids":["cpe:2.3:a:ex_aws_sns_project:ex_aws_sns:*:*:*:*:*:*:*:*"],"cwe_ids":["CWE-295"]},"references":[{"type":"ADVISORY","url":"https://github.com/ex-aws/ex_aws_sns/security/advisories/GHSA-8jgf-23q5-x7xx"},{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-47074.html"},{"type":"FIX","url":"https://github.com/ex-aws/ex_aws_sns/commit/1853d280b152d10384a1e21a22cf22152a60be48"},{"type":"PACKAGE","url":"https://hex.pm/packages/ex_aws_sns"}],"affected":[{"package":{"name":"ex_aws_sns","ecosystem":"Hex","purl":"pkg:hex/ex_aws_sns"},"ranges":[{"type":"SEMVER","events":[{"introduced":"2.0.1"},{"fixed":"2.3.5"}]}],"versions":["2.0.1","2.1.0","2.2.0","2.3.0","2.3.1","2.3.2","2.3.3","2.3.4"],"database_specific":{"source":"https://cna.erlef.org/osv/EEF-CVE-2026-47074.json"}},{"ranges":[{"type":"GIT","repo":"https://github.com/ex-aws/ex_aws_sns","events":[{"introduced":"a7ec21880943f4dac1d59bda557db0ffcd2b61fa"},{"fixed":"1853d280b152d10384a1e21a22cf22152a60be48"}]}],"versions":["v2.3.3","v2.3.2","v2.3.1","v2.3.0","v2.2.0","v2.0.1"],"database_specific":{"source":"https://cna.erlef.org/osv/EEF-CVE-2026-47074.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"}],"credits":[{"name":"Peter Ullrich","type":"FINDER"},{"name":"Bernard Duggan","type":"REMEDIATION_DEVELOPER"},{"name":"Jonatan Männchen / EEF","type":"REMEDIATION_DEVELOPER"},{"name":"Jonatan Männchen / EEF","type":"ANALYST"}]}